Heres this dude from the evom forums thats converting his RA to AWD, I know its a diferent car, but at least its a story that will hit close to home for you.
http://forums.evolutionm.net/showthread.php?t=262790

 

That's what I'd like to see. RA already proved that it could be done. I say screw the thought of weight, unless you remove panels and sub them with CF like RA did.
I can picture a 4G at full weight with 500-600 ponies being a FUN car!! If the 4G feels like a pig with what it's got in it, doubling that or even tripling that would make that car feel light. Ask me how I know....